Bobbin winders for sewing machines



April 26, 1960 Fig.\

WI TN E 55 M. F. IVAN KO 2,934,282

BOBBIN WINDERS FOR SEWING MACHINES Filed Nov. 2, 1956 Fig.2

INVEN TOR. Michael E lvanko 5 E ZTTORNEY United States Patent BOBBIN WINDERS FOR SEWING MACHINES Michael F. Ivanko, Stratford, Conn., a'ssignor to The Singer Manufacturing Company, Elizabeth, N.J., a corporation of New Jersey Application November 2, 1956, Serial No. 620,136

2 Claims. (Cl. 242-22) This invention relates to bobbin winding attachments for sewing machines, and more particularly to a bobbin winding attachment adapted to be driven by the belt by which the'sewing machine is driven.

It is an object of this invention to provide an improved bobbin winding attachment for a sewing machine including a driven wheel shiftable manually into an operative position in engagement with a belt and shiftable automatically into an inoperative position out of engagement with the belt after a predetermined quantity of thread has been wound.

It is another object of this invention to provide a means for regulating the proximity of the driven wheel to the belt in the operative position of the wheel without disturbing the means mounting the bobbin winding attachment on the sewing machine.

With the above and other objects and advantages in view as will hereinafter appear, this invention comprises the devices, combinations, and arrangements of parts hereinafter described and illustrated in the accompanying drawings in which:

Fig. 1 is a side elevational view of a bobbin winding attachment and includes a portion of the sewing machine to which the attachment is secured as well as a fragment of the belt by which the sewing machine and the bobbin winder are driven, and

Fig. 2 is a rear elevational view of the bobbin winding attachment of Fig. 1.

In the drawings, the bobbin winding attachment of this invention is illustrated as applied to a sewing machine frame 11 formed with a raised attachment mounting boss 12 which is slotted transversely as at 13. The various parts of the attachment are carried on a base 14 formed transversely with a tang 15 seated snugly into the machine frame slot 13, whereby confining the attachment base to movement with respect to the machine frame only in the direction of the slot 13. The attachment base is formed with elongated slots 16-16 one at each side of the tang 15 to accommodate fastening screws 17-17 by which the attachment base may be secured to the sewing machine.

The attachment base is formed with a projecting lug 18 having a threaded hole 19 for a pivot screw 20, and a counterbored recess 21. Within the recess is disposed a coil spring 22 of which one extremity is anchored on the projecting lug 18 and the other in a frame 23 journaled on the pivot screw 20. A lock nut 24 serves to lock the pivot screw securely in place and to maintain the proper clearance between the lug 18 and the frame 23 so as not to cause binding at the pivotal connection therebetween. Journaled in the frame 23 substantially parallel to the pivot screw 20 is a shaft 25 formed at one end with a diametrically split portion 26 which serves in the conventional fashion to grip a bobbin to be wound. East on the shaft 25 between branches 27, 28 of the frame 23 is a belt-engaging wheel 29. As indicated in the drawings the peripheral shape of the wheel 29 is preferably made to conform with the shape of a so-called V belt 2,934,22 Patented Apr. 26, 1960 ice 33, however, it will be understood that a belt of any cross sectional configuration may be used with the device of this invention so long as the peripheral shape of the beltengaging wheel is formed accordingly.

The branch 28 of the frame 23 is formed with an arm 31 threaded at its free extremity to accommodate a pivot screw 32 by which the arm is joined to one link 33 of a pair of toggle links 33, 34 pivoted together by a rivet 35. The toggle link 34 is pivoted in turn by a rivet 36 to an anchor member in the form of a link 37, apertured to accommodate a clamp screw 38 formed with an enlarged head 39. The clamp screw 38 is threaded into a lug 40 extending from the attachment base 14 on an axis substantially parallel with the axisof the pivot screw 20 of the frame 23.

The toggle link 34extends on both sides of the rivet 35 joining the toggle links 33, 34 and is formed with a finger grip portion 41 which is struck out to one side. The finger grip portion provides not only a means for manually straightening the toggle links, but it also provides a stop engageable with the link 33 to determine the straightened position of the toggle links, as best illustrated in Fig. 1, in which the links are locked together at an oblique angle slightly beyond the perfectly straightened position. The toggle link 33 is also formed with a tang 42 struck out at one side into which is threaded an adjusting screw 43 supporting a toggle-releasing spring member 44 formed with a spring finger 45 extending alongside the split bobbin gripping extremity 26 or" the shaft 25 and, when a bobbin is mounted on the shaft 25, is adapted to extend between the flanges of the usual bobbin.

The spring finger 45, when engaged by a thread mass being wound on the bobbin, causes the toggle link 33 to be turned clockwise as viewed in Fig. 1, thus causing the toggle linkage 33-34 to be broken and carrying the frame 23 in a counterclockwise direction under the action of the coil spring 22 to shift the wheel 29 out of operative engagement with the belt 30. By means of the adjusting screw 43, the position of the spring finger may be shifted so as to throw the bobbin winder out of operative winding position after any predetermined mass of thread has been wound on the bobbin.

The fastening screws 17 and the elongated slots 16 in the attachment base 14 provide for a limited range of axial adjustment of the belt-engaging wheel 29 so that the wheel may be shifted to a position in which the plane of the wheel coincides with a plane containing a limb of the sewing machine driving belt.

When the toggle links 33, 34 occupy the straightened position as illustrated in the drawings, the wheel 29 should occupy a position as shown in Fig. l in operative engagement with the belt. In order that such a position of operative engagement may be attained with great nicety, the clamp screw 38 is first loosened so as to free this anchor link 37 for turning movement about the screw 38. The toggle links 33, 34 in straightened position may then be shifted bodily so as to adjust the position of the frame 23 to bring the wheel 29 properly into engagement with the belt 30. The clamp screw 38 is then tightened so that the enlarged head 39 thereof locks the anchor link in the selected position of angular adjustment.

The proximity of the wheel 29 to the belt 30 in the operative position of the parts is of critical importance to the proper operation of the bobbin winding device, and the proper relationship between the wheel and the belt will be affected by many factors such, for instance, as the tension in the belt, so that it may be necessary to reestablish quite frequently the proper relation between the wheel and the belt. The angularly adjustable anchor link 37 and the clamp 38, 39 for securing the anchor link in selected position of angular adjustment, therefore, of

fer a quick and convenient means for establishing the desired driving relationship therebetween.

Having thus set forth the natureof theinvention, what I claim herein is: g

1. A bobbin winding attachment for a belt driven sewing machine comprising, an attachment base adapted to be secured to said sewing machine, a swinging frame pivoted to said attachment base, a shaft journaled'in said frame,

mass wound on said bobbin gripping means for breaking said toggle links. k g

2. A bobbin winding attachment for a belt driven sewing machine comprising, an attachment base, a swinging frame pivoted to said attachment base, a shaft journaled in said swinging frame and formed with a bobbin accommodating extremity, a belt engaging wheel fast on said shaft, said attachment base being formed with a fastening screw accommodating slot elongated in a direction parallel with the axis of movement of said swinging frame, a fastening screw in said elongated slot adapted to be threaded in said sewing machine for securing said attachment to said machine in a selected position in which the plane containing the belt engaging wheel coincides with a plane containing one limb of the sewing machinedriving belt, an anchor link pivoted to said attachment base, a pair of toggle links pivotally connected between said anchor link and said swinging frame, means associated with said toggle links and responsive to the diameter of thread mass wound on the bobbin accommodating extremity of said shaft for breaking said toggle links, and means for locln'ng said anchor link against pivotal movement with, respect to said attachment base and in selected position of angular adjustment thereon in which the belt engaging wheel is disposed in operative engagement with said belt when said toggle linkage occupies a straightened position.

References Cited in the tile of this patent UNITED STATES PATENTS 809,911 Eames et a1. Jan. 9, 1906 1,475,597 Ringe Nov. 27, 1923 2,631,472 MacDougall Mar. 17, 1953 2,714,828 Britton Aug. 9, 1955 

